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1.
南极周边海域蕴藏着丰富的南极磷虾资源,其开发潜力受到世界各国的关注。为此,本研究基于南极海洋生物资源养护委员会(CCAMLR)统计数据分析了近几年南极磷虾渔业国家发展状况,并研究了南极磷虾渔业捕捞结构的变化特点。结果发现:(1)受捕捞技术及装备的限制,南极磷虾传统渔业国家——波兰、日本及乌克兰等正逐渐淡出开发行列;(2)随着挪威、中国及智利等新兴国家的加入,南极磷虾入渔船舶和渔业产量呈上升趋势;(3)南极磷虾全年均有生产,其中3—9月份渔获产量占总产量的70%—90%;(4)受综合环境因素和新的渔业管理措施影响,CCAMLR 48.1、48.2和48.3小区渔获产量年间波动变大,渔场选择难度增大;(5)传统的大规模科学调查模式已不适应该资源变化与渔业管理的要求,科学性渔业调查将成为今后南极磷虾资源调查与评估的重要补充。 相似文献
2.
In an effort to control escalating fishing effort, a quota management system (QMS) of individual transferable quotas (ITQs) has recently been introduced in the Tasmanian rock lobster fishery. We outline and compare the input controls system in place before the introduction of a QMS, and we discuss the operation of the QMS to the end of its first full season in February 1999. We find cautiously for a successful introduction of a QMS as catch, effort and catch rate data tend towards what fishery managers believe to be bio economically sustainable levels. 相似文献
3.
In Malawi, fishing community user groups known as beach village committees, traditional chiefs, government officers, and fishers are the key players in fisheries management. Fish catch trends at the Elephant Marsh Fishery in southern Malawi are declining. Based on interviews and participant observation, this article uses an actor-based framework (known as Action-in-Context) to unveil the issues that are crucial in devising a sustainable governance system for the fishery. We establish and propose that the key social variables for the design of a three-pillared (locally based, weak, and amorphous) resilient institution for sustainability of the Elephant Marsh Fishery are (i) the social reputation of the leaders of local fishery institutions (beach village committee leaders), and (ii) the power dynamics between traditional chiefs and these local fishery leaders. We end the article by exploring the implications of the findings on the sustainability of the fishery under rising resource pressure. 相似文献
4.
2007年夏季和秋季,按照GB11607-1989《渔业水质标准》和GB3838-2002《地表水环境质量标准》,对陕西黄河湿地渔业水域环境质量的主要理化指标进行了现场监测,对渔业水域的主要水生植物进行了调查。结果表明:陕西黄河湿地渔业水域的池塘和大水面硫化氢(H2S)含量均符合标准,池塘和大水面的总磷(TP)及总氮(TN)均不符合标准。池塘和大水面渔业水域环境质量呈明显的富营养化现象,池塘比大水面富营养化现象严重,但湿地大水面的主要理化指标优于池塘,湿地大水面渔业水域生长的水生植物芦苇Phragmites australis和香蒲Typha orientalis对TP和TN具有一定的净化作用,通过监测分析提出了湿地渔业水域的保护措施。 相似文献
5.
K. F. Walker I. G. Dunn D. Edwards T. Petr H. Z. Yang 《International Journal of Salt Lake Research》1995,4(3):169-222
Quinghai Hu is a large, high-altitude, saline lake in north-western China, and supports a fishery based on an endemic species of naked carp (snow trout). The fish take seven years to attain maturity and a marketable weight of 300 g, and have a lifespan of 14–21 years under the present fishery regime. They seasonally migrate from the lake to spawn over the gravel beds of inflowing rivers, but these areas have been reduced by weirs and irrigation diversions and recruitment may have declined. The population may have been affected also by a 1.85-m fall in the lake level over the past 30 years, and by associated changes in salinity. The fishery was opened to large-scale exploitation in 1958. Yields declined sharply (max. 28,523 tonnes, 1960) as the larger, older fish were removed, and then more slowly (min. 2523 tonnes, 1983). Since 1987 the fish factory has been limited to an annual quota of 1200 tonnes, taken by a fleet of four pair trawlers. Another 800 tonnes are taken by licensed fishermen, mainly using gill nets, and perhaps 1000 tonnes are taken illegally. The estimated total catch in 1992 was 3000 tonnes. New trawlers introduced in 1989–90 substantially increased the factory's catch per unit effort, and in 1990 the quota was virtually filled in one month in a zone within 20 km of the factory. Although this could suggest that the stocks will be conserved if the quota is retained, at least half of the catch in 1989–92 consisted of immature individuals. Trawling operations recently were suspended following a further decline in the catch after 1992. While the new trawlers are capable of a major increase in effort, neither the changing environment, the fish stocks or the present markets favour intensified pressure. Gillnets may provide better control over the minimum size limit and may cause less damage than trawling. Other options to improve the viability and profitability of the fishery include improvements in handling, processing and marketing. Failure to develop the fishery may encourage attempts to introduce exotic fish, at some risk to survival of the local species. 相似文献
6.
IAN T. JOYCE 《Geographical review》1997,87(4):484-503
ABSTRACT. The spiny-lobster fishery, the most valuable fishery in Cuba, is unique among those in major lobster-producing countries because of its combination of strong central control and absence of standardization and mechanization in fishing gear. Cooperation rather than competition among fishing vessels is promoted by exclusive fishing zones and fleet organization. These measures, along with the use of storage centers, simple vessels, and inexpensively constructed fishing gear, have promoted spatial rationality and cost reduction in the fishery and made it one of the most successful spiny-lobster fisheries in the world. 相似文献
7.
非洲沿海国家海洋渔业资源开发利用现状 总被引：1，自引：0，他引：1
根据联合国粮农组织提供的1950-2015年非洲渔获生产统计数据，结合Fishbase提供的相关鱼种营养级（Trophic level, TL）以及Sea Around Us Project Database提供的海洋无脊椎动物营养级，探讨了1950-2015年北非、东非、南非、中非和西非的沿海国家渔获物平均营养级（Mean trophic level, MTL）的变化情况，以此来判定非洲沿海国海洋渔业资源的开发利用现状。结果表明：非洲沿海国家的海洋渔业资源开采大致经历开发不足、快速开发、过度开发阶段，1984-1991年，北非地区的海洋渔业资源遭到一定程度的破坏，高营养级渔业资源渔获量减少了33.5%，MTL由3.44降低到3.25；东非地区渔获量较其他4个区域低，目前，大部分鱼类资源处于充分捕捞利用状态；南非地区在21世纪初发生“捕捞降低海洋食物网”现象，2004-2015年，MTL恢复小幅上升趋势，渔业均衡指数（Fishing-in-balance index, FIB）趋于平稳；2013-2015年，中非地区的MTL与FIB均呈下降趋势，说明产量的增加速度不足以弥补营养级的降低，生态系统结构功能开始遭到破坏；1950-2015年，西非地区的渔获量不断增加，从上世纪60年代开始，过度捕捞现象愈加严重，低营养级鱼类数量占比呈先减少后增加趋势，2001-2012年，MTL波动下降，FIB平稳变化，说明MTL的下降由产量的增加而抵消。21世纪以来，部分北非、南非与西非沿海国家加强了资源管理，渔业资源状况有所好转。研究认为：渔获物平均营养级的下降主要由过度捕捞引起，非洲国家的管理不力加重了过度捕捞现象，建议非洲各国尽快建立起基于渔获物统计的海洋渔业资源实时监测系统，以便掌握捕捞活动下的鱼类群落结构的变动情况。 相似文献
8.
该文对我国海洋渔业资源与开发现状进行评价,并在我国社会经济发展及技术条件允许的基础上,提出将传统的猎捕型渔业生产方式转变为管理型,以及进行海洋农牧化建设 相似文献
9.
基于中国南极磷虾渔业科学观察员收集的数据,利用广义可加模型（GAM）,对2009—2010渔季和2010—2011渔季夏秋季南奥克尼群岛周边水域南极磷虾渔场时空分布及其与表温和海况之间的关系进行了研究。结果表明,GAM模型对单位捕捞努力量渔获量（CPUE）总偏差解释率为41.78%,其中贡献最大的为月份,贡献率为15.53%;奥克尼群岛水域CPUE分布模式均有明显的月份差异。1月份平均CPUE值最低,而4月份平均CPUE值最高,各月份平均CPUE存在显著性差异。渔场主要集中在60°12′—60°30′S,45°30′—47°30′W。南极磷虾作业渔场的适宜海水表温范围为0.1—1.8℃,最适表温范围为0.5—1.5℃。各海况等级间及不同渔船的平均CPUE均存在显著性差异。逐步GAM模型分析结果表明,影响CPUE的因子按重要性从大到小依次为月份、渔船、经度、海表温度、纬度和海况。 相似文献
10.
中国海洋渔业资源可持续利用的动态评价与空间分异 总被引：1，自引：1，他引：0
运用基于多智能体遗传算法的投影寻踪模型和核密度估计模型,对2003~2012年中国沿海11个省市（不含港澳台）海洋渔业资源可持续利用水平的时空格局演化进行测度。研究结果表明：从投影方向上看,捕捞技术、捕捞强度和渔业产业结构等,逐渐上升为影响海洋渔业资源可持续利用水平的重要因子;从时空格局上看,上海的海洋渔业资源可持续利用属于高水平区板块,天津、河北、江苏、浙江和广西属于中等水平区板块,辽宁、山东、福建、广东和海南属于低水平区板块;从总体上看,海洋渔业资源可持续利用呈现不可持续性,具体表现为时间演化可持续,空间演化不可持续,时空演化呈现出不可持续的两极分化趋势。未来高水平区板块应保持原来的发展模式,中等水平区板块的可持续利用路径选择是保中争高,低等水平区板块的可持续利用路径选择是追中攀高。 相似文献
11.
以现代渔港经济区理念看广东惠来县神泉港的发展 总被引：1，自引：0，他引：1
分析了现代渔港经济区的内涵、构建思路与关键问题,指出神泉渔港发展所面临的问题、发展的优势与发展的契机,并结合现代渔港经济区理念,具体探讨了神泉现代渔港经济区的发展设想、发展策略与对策措施。 相似文献
12.
休闲渔业是美国最受欢迎的户外活动之一,在发展过程中为美国创造了巨大的经济和社会效益,并形成多主体参与的治理机制。文章在分析美国休闲渔业发展现状的基础上,运用最邻近指数、缓冲区分析、泰森多边形和关联维数测度,对佛罗里达州休闲渔业资源分布特征进行空间分析。结果显示,美国休闲渔业形成以淡水为主、咸水为辅的发展格局,其中佛罗里达州休闲渔业资源呈现集聚式、非均衡分布特征,80%的垂钓点位于海岸线20 km以内,各垂钓点之间形成紧密的关联作用。联邦政府、地方政府、行业组织和休闲渔业参与者之间形成的多中心治理模式,能够匹配美国休闲渔业大区域分散、小区域集聚的空间分布特征,适应参与主体多样化、需求差异化的发展需要。有鉴于此,针对中国休闲渔业存在的问题,提出应通过借鉴美国“自下而上”的多中心治理机制,建设服务型政府、行业协会灵活增权以及休闲渔业企业融合创新等措施,推动中国休闲渔业科学管理和高质量发展。 相似文献
13.
中国制造业分布的地理变迁与驱动因素 总被引：7，自引：1，他引：6
近年来中国制造业分布格局呈现出新的动向。以2004-2005年为转折点,以食品轻纺行业为主的部分制造业部门开始从沿海省份向中西部省份转移,北京、天津、上海、浙江、广东、福建等省份的产业份额明显下降,安徽、江西、湖南、河南、四川等中西部省份的产业份额趋于增加。在地市尺度上,制造业分布变化呈现出"西进北上"的特点,具体表现为产业份额从沿海发达城市转向沿海省份内部发展相对滞后的地市、以及中西部省份内部产业基础较好且本地市场规模较大的地市。中部地区的重点开发区域已成为承接产业转移的重要载体。沿海地区劳动力、土地等要素成本上升导致要素成本的区域差异不断扩大,与此同时中西部地区市场邻近和供给邻近逐步得到改善。沿海地区和中西部地区之间要素成本差异的扩大和贸易成本差异的缩小,使得贸易成本和要素成本的均衡关系发生逆转性变化,这是驱动中国产业分布地理变迁的核心因素。 相似文献
14.
In this paper we report on a collaborative inquiry involving a human geographer and a mathematician‐cum‐data modeller. Our example is the existence and nature of a possible ‘skipper effect’ in the Tasmanian commercial rock lobster fishery. The term ‘skipper effect’ is used to describe the supposedly variable contribution of boats' skippers to catch. Following an introduction of the fishery and an outline of our research, we briefly introduce the skipper effect. We also discuss an approach to conceptualising knowledge before moving to our case study which we treat both qualitatively and quantitatively. Possible implications of the combination of qualitative and quantitative research for fishery management are also presented. In so doing, we relate a piece of work that is both multi‐method and multi‐disciplinary. 相似文献
15.
渔业配额制度是在渔业资源过度捕捞所导致的渔业危机和传统的投入控制管理失效的历史背景下,基于渔业资源生态特性而构建的一种产出控制的渔业管理模式。它是在总可捕量基础上发展起来的,并在冰岛、新西兰等国家得以成功实施。中国学者对于配额制度的法律特性持不同观点,认同其准物权的特性是主流观点。资源的生物特性以及制度的实质内涵告诉我们,无论是国际配额还是国内配额,制度要想取得实效,必须牢牢遵循不得超越总可捕量的共同义务这一要旨,通过落实有限准入、加强监管等多种手段来保障这种共同义务的履行,才能实现资源的永续利用。 相似文献
16.
近代长江上游地区人口迅速增长,鱼类资源开发力度增强,有时甚至成为人们赖以活命的依靠。有害渔具渔法的使用、贩卖鳅鳝、毒捕放生区域鱼类等行为使得破坏鱼类资源的问题不断凸显。与此同时,民众的放生,乡规民约和国家明令禁止捕鱼的行为,对保护鱼类资源起着积极的作用。长江上游地区鱼类资源在很长时期内并未进入国家的主流视野,对其管控力度不强,保护的目的多出于原始生命观、避免灾祸等思想。民国时期渔业经济利益逐渐受到重视,国家对鱼类资源的管控力度逐渐增强,保护目的更加多元化,维护渔业经济利益成为主要目的。 相似文献
17.
Problems of Artisanal Marine Fishermen in Ghana: The Way Ahead 总被引：1，自引：0，他引：1
John Victor Mensah & Barima Kwabina Antwi 《Singapore journal of tropical geography》2002,23(2):217-235
Marine fishing is an important traditional economic activity of the coastal communities in Ghana and contributes over 80 per cent of the total fish catch. The traditional sector accounts for over 75 per cent of the marine catch. The small-scale artisanal marine fishing communities, which contribute less than 30 per cent of the traditional sector landings, are generally characterised by low levels of production and, hence, low incomes, poor living conditions and chronic indebtedness. Based on field data on artisanal fishing communities in the Ahanta West and Gomoa districts, this paper summarises the chronic problems of artisanal fishermen that perpetuate their precarious existence in the coastal environment. Overcoming the problems of these increasingly marginalised and migrant communities calls for the provision of supplementary employment opportunities, improved social services and the formation of solidarity groups to enhance access to micro credit. These would require technical and management training as well as support services from government and non-governmental organisations (NGOs). 相似文献
18.
南海渔业开发为维护我国渔业利益和海洋权益发挥了重大作用,近年来急速衰退的渔业资源和不断升温的冲突态势亟须寻找治理革新的突破口。基于此,首先从南海渔业资源环境特点、南海渔业资源开发利用历史沿革与现状,辨析南海渔业时空格局,指出南海渔业资源环境具有跨越国家界线的互通性、整体性与相互依赖性,且周边国家和地区对南海渔业高度依赖,并已经造成资源环境严重衰退。其次通过对南海渔业冲突和南海渔业资源治理所面临的挑战的梳理,指出引发南海渔业冲突的条件今后很可能更加普遍,亟需南海各方共同面对渔业可持续性危机,而南海地区面临的渔业资源环境退化、系统认知不足、区域协作有限等共性挑战与利益诉求,可成为促进区域合作的纽带。最后以区域渔业资源治理为抓手,提出了构建南海命运共同体的建设思路：从推动绿色水产养殖、增强资源环境修复、深化科研共享等方面开展务实的渔业资源治理合作;在区域、国家、地方层面完善跨尺度的海洋治理措施落实体系,协同提升国家层面的顶层涉海涉渔政策设计,强化地方、私营部门和公民个人在南海区域共建中的作用;从建立健全区域组织和完善区域海洋法制推动构建区域层面合作治理体系。 相似文献
19.
Mexican and Central American immigrant communities in the boom and bust housing markets of the 2000s
Molly M. Scott 《Urban geography》2013,34(1):29-43
Classic immigrant enclaves, largely voluntary and temporary, have historically served as a strong platform for integration in United States metropolitan areas. However, trends in the early 2000s, including new destinations and skyrocketing housing costs, may have reshaped the landscape, particularly for numerically dominant immigrant groups with very low socioeconomic status. In this article, I use data for 56 metropolitan areas and 31,563 census tracts from the 2000 Census and the 2005–2009 American Community Survey to examine the relationship between the change in concentration of Mexican and Central American immigrants and the characteristics of neighborhoods in 2000. The analyses suggest that, across metropolitan areas, these immigrant communities consolidated in neighborhoods with low home values, adequate but overcrowded housing, relatively small shares of their own immigrant group, and large shares of other Hispanics. Demographic dynamics may have weakened immigrant support networks, leaving Mexican and Central American immigrants vulnerable, particularly in a subset of metropolitan areas where this population grew most substantially outside the central cities. 相似文献
20.
Nesar Ahmed Sanzidur Rahman Stuart W. Bunting Cecile Brugere 《Singapore journal of tropical geography》2013,34(1):86-102
Socio‐economic and ecological challenges faced by the small‐scale fishers dependent on the Old Brahmaputra River, Bangladesh are assessed using a combination of questionnaire survey, co‐monitoring of fish catch, focus group discussions and key informant interviews. Results reveal that the fishers are involved in professional, seasonal or subsistence fishing. Fish catches from the river have declined significantly because of overfishing, destructive use of fishing gear, water pollution, siltation, rapid urbanization and human encroachment, thereby threatening the health of the river ecosystem as well as the future of small‐scale fishing. We evaluate various social, economic and ecological challenges faced by the fisher communities. We propose a conceptual framework that recognizes linkages among social, economic and ecological aspects in devising a sustainable river fisheries management system. We recommend effective legal enforcement of policies and regulations, strong institutional collaboration and active fisher community participation in management to ensure sustainable use of the resource base. 相似文献